Hyperthermia is an uncontrolled elevation of body temperature exceeding the body's ability to dissipate heat. Hyperthermia can result in dangerously high core temperatures and can rapidly become fatal. Common causes include heat stroke, malignant hyperthermia, serotonin syndrome, neuroleptic syndrome, a few endocrine emergencies as well as numerous intoxications. Rapid diagnosis and prompt cooling are pivotal, since the condition triggers a cascade of metabolic events which may progress to irreversible injury or death. Ice-water immersion and evaporative cooling are the methods of choice.